New Device Cleans Water With Light - Saves Lives In Developing Countries

An off-shoot of Berkeley Lab's research into fluorescent lighting could prove to
be a life-saving gift to the children of developing countries. More than 400
children die every hour as a result of water supplies being contaminated with
such diseases as cholera, typhoid, and dysentery. Berkeley Lab scientists have
developed a simple device that uses the same ultraviolet radiation (UV light)
produced in fluorescent lamps to disinfect water. This device, which is a
stainless steel chamber about the size of a microwave oven, can be fitted
directly into the plumbing of a water source such as a community hand pump. As
water passes through the chamber, it is bathed in UV light, which kills viruses,
molds, and other pathogens by inactivating their DNA.

The system can
disinfect water at a rate of four gallons per minute (similar to the flow from a
typical bathtub spout in the United States) at a cost of pennies per ton. It is
currently being field-tested in India, where recent cholera epidemics from
contaminated well water have killed thousands of children.

"The device has
tremendous potential to save lives," says physicist Ashok Gadgil, a researcher in
the Lab's Energy and Environment Division who is developing the device. "It gives
communities in developing countries a central place for collecting disinfected
water." Last fall, Lab researchers shipped devices to the Virgin Islands for
disaster relief in the wake of devastating hurricanes that left much of St.
Thomas and neighboring islands without safe drinking water.

As an added
benefit, the use of these UV devices could replace the common practice in
developing countries of boiling water over wood-burning stoves, which contributes
to the problem of deforestation.